“I did bad things,” he allegedly told a manager at a homeless shelter in East New York where he was staying on the night of the slaying

“The devil made me do it,” he added.

St. Hubert, arrested Wednesday night, has not confessed. When asked how his fingerprints ended up in the Boulevard Houses elevator in East New York, he replied, “The devil put my prints there.”

When he was busted, he was in the process of scrawling graffiti on a stop sign near his mom’s home in Jamaica, Queens.

He wrote, “$ KILLZZ I WILL BK” with a winking smiley face. “BK” are the initials for his gang name, “Boy Kangaroo,” the sources said.

Cops saw him do this and took him into custody.

He was hit with charges including murder and attempted murder.

Onlookers yelled, “Murderer! You deserve death!” as St. Hubert was taken from the 90th Precinct station house to be arraigned.

Police had found St. Hubert wandering blocks from his mom’s house at around 8 p.m. by tracking his cellphone.

He was carrying an 8-inch steak knife similar to the one used to kill Prince Joshua and maim Mikayla.

It is unclear whether St. Hubert was intending to harm his mother, whom he choked in 2009.

St. Hubert is suspected of stabbing 18-year-old Tanaya Grant-Copeland, 18. to death last Friday in East New York with a similar murder weapon. Cops also believe St. Hubert stabbed Kyle Moore, a 53-year-old homeless man, early Wednesday morning on a Chelsea subway platform.